Currently, in the field of wireless communications, a bandwidth of a wireless network is limited. A quantity of users that can access each base station is limited. When the quantity of users is increased, a bandwidth available to each user is decreased, resulting in degradation of service quality of the wireless network. In view of this situation, a Wi-Fi network is widely established currently to implement short-distance network access, to mitigate a user capacity limitation confronting the base station.
Wi-Fi is generally known as wireless broadband and is a term published by an organization named “Wireless Ethernet Compatibility Alliance” (Wireless Ethernet Compatibility Alliance, WECA). Wi-Fi is translated as wireless fidelity in Chinese. It is a short-distance wireless transmission technology and supports radio signals for accessing the Internet within a scope of hundreds of feet. With development of technologies and emergence of standards such as IEEE 802.11a and IEEE 802.11g, currently the IEEE 802.11 standards are collectively called Wi-Fi. From an application perspective, a user first needs to have a user-end apparatus that is compatible with Wi-Fi before using Wi-Fi.
On a current Wi-Fi network, there are still problems with terminal authentication. A conventional terminal authentication solution implements authentication and maintains an authentication result in a session (session) manner. Every time a user uses the Wi-Fi network, the user needs to manually enter information such as a user name and a password. Operations are cumbersome and a login page in a browser cannot be closed. Security of this authentication process is poor, and an inherent risk of the conventional webpage manner, for example, interception of the user name and password by a third party, may exist. In addition, whether the user is online or offline is determined in a session refreshing manner, resulting in poor instantaneity.